A friend taught me to use a T post driver as a T post puller. It’s a pretty neat trick that you can use the same tool for both operations. You place the closed end on the ground and brace the open end under a lug to use the driver like a fulcrum. With the driver between you and the T post, pull back hard on the post until it pops up a bit and then reset the open end of the driver beneath a lower lug and keep at it until it can be lifted by hand.